1. Field of the Invention
This invention relates to a starch-based biodegradable material composition, more particularly to a starch-based biodegradable material composition including a biodegradable polyester selected from at least one of an aliphatic polyester of polybutylene succinate and an aliphatic-aromatic copolyester
2. Description of the Related Art
A conventional biodegradable material composition usually includes a native starch blended with a polymer so as to enhance the mechanical strength of the biodegradable material composition. However, the native starch has two large molecular groups of amylose and amylopectin, which can result in poor blending with the polymer due to stereo-hindrance of the molecular structure of the native starch.
It is known in the art to use a chemically modified starch to enhance the blending efficiency. However, chemical modification of the native starch is relatively complex and has drawbacks, such as undesired chemical residue and low microorganism degradable rate.
Taiwanese patent no. 552290 discloses a biodegradable material composition including an enzyme-hydrolyzed starch, which is prepared by hydrolyzing a native starch using a starch-hydrolyzing enzyme, a polyvinyl alcohol, a plasticizer, and a property-improving agent. Although the biodegradable material composition has excellent biodegradability, films made therefrom have a relatively poor tensile strength and can only be used for production of foam materials or plate materials.